Portable telephone



FIG. 1 is a front, bottom, and left side perspective view showing our new design for a portable telephone with the cover closed;

FIG. 2 is a front, bottom, and left side perspective view showing our new design for a portable telephone with the cover open;

FIG. 3 is a right side elevation view of the portable telephone according to FIG. 1;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is top plan view thereof. 

The ornamental design for a portable telephone, as shown and described. 